It is the irreversible and permanent cessation of
all brain functions. Brain can no longer send messages to the body to perform vital functions like breathing, sensation, obeying commands etc.
Such persons are kept on artificial support (ventilation) to maintain oxygenation of organs so that the organs are in healthy condition until
they are removed. Most cases of brain death are the end result of head injuries, brain tumours patients from Intensive care units. Organs of
such patients can be transplanted in organ failure patients to provide them a new lease of life.